The present invention relates generally to fuel filling systems on vehicles and more particularly to venting of the fuel filling systems.
Fuel systems on vehicles generally require venting. In some automotive vehicles, the fuel tank is vented to the front of the vehicle near the engine compartment even though the fuel tank is near the rear of the vehicle. The venting may be, for example, connected to a transmission vent line. This type of venting arrangement requires a relatively long length of fresh air line and multiple clips to support the flexible line. This arrangement has the potential to end up with a pinched or crimped line.
In order to avoid these problems, others have attempted to vent the fuel system via a fill pocket area. A first configuration vents inside the fuel pocket by employing a double walled fill pipe. The vent is located under the lip of the fill pipe, with the fill pocket being tightly sealed against dust and debris. However, the cost of a double walled pipe is more than is desirable, and the cost and complexity in sealing the fill pocket area is undesirable. A second configuration has an open vent located near the top of the fill pocket housing. However, this open vent allows debris to fall into the fill pipe during fueling, which allows the debris to get into the fuel system.